What is the difference in elevation between city #2 and #4? City 2- 42 feet below sea level

City 4- 49 feet above sea level

A) 6 feet
B) 7 feet
C) 81 feet
D) 91 feet

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.